This invention relates to smoking articles such as filter cigarettes, and in particular to such smoking articles having means for rotatable adjustment.
Cigarettes having adjustable regions have become subjects of increasing interest, particularly in situations wherein the adjustment of the air dilution value of filter cigarettes is desired. Known methods for providing adjustments to the air dilution value of filter cigarettes generally involve making one or more openings through a substantially air impermeable filter plug wrap, through the substantially air impermeable tipping paper and through a corresponding sleeve which is placed over the tipping paper, which sleeve is movable either rotatably or axially in order to select the degree to which the sets of openings are in registry.
Numerous known methods for providing adjustments to the air dilution value of filter cigarettes suffer from various problems. For example, a movable sleeve may be easily inadvertently removed from the cigarette by the smoker and not readily replaced. Furthermore, the degree of registry between the sets of openings can be inadvertently destroyed by slight axial movement of the sleeve. Accordingly, the air dilution value, once set by the smoker, is not insured to any degree of consistency.
U.S. Pat. No. 4,532,943 to Nichols et al proposes a filter cigarette having a filter plug having a mouthend segment and a tobacco rod end segment, wherein the two segments are axially connected for rotation about the longitudinal axis of the cigarette. Typically, in such a filter, the two segments are defined by a circumferential cut in the filter plug. However, a cigarette having a means for adjustment which does not require a segmented filter for rotation is clearly desirable.
U.S. Pat. No. 4,570,649 to Nichols et al proposes a variable dilution filter cigarette wherein the filter plug includes a circumscribing wrap in the form of three bands. The bands at the mouthend and rod end of the filter plug are attached to the filter, and the central band is rotatable about the plug. Tipping paper in the form of two bands attaches the filter plug to the rod while providing for rotation of the plug such that an opening in the rod end band of the plug wrap can be positioned in varying degrees of alignment with an opening in the tipping paper. However, the filter cigarette proposed in U.S. Pat. No. 4,570,649 to Nichols et al has a limited degree of rotation. In addition, manufacture of such a filter requires additional equipment to rotate the filter element into the full flavor position after the air dilution slots or vents are provided. Furthermore, cutting of filter tow within a filter is not particularly desirable in certain applications.
It would be highly desirable to provide a filter cigarette having an easily settable, rotatably adjustable filter region being capable of having unlimited rotational ability. In addition, it would be highly desirable to provide a filter cigarette having an adjustable filter region, which cigarette is relatively easy to manufacture at a commercial scale.